File with endless carriers and double guiding track



Jan. 17, 1967 ZIPPEL 3,298,536

FILE WITH ENDLESS CARRIERS AND DOUBLE GUIDING TRACK "Filed Aug. 21, 1964 5 Sheets-Sheet 1 I m VENTOR. 62026 A1 rez .Z/PPL ATTOE/i/KYJ Jan. 17, ZIPPEL I FILE WITH ENDLESS CARRIERS AND DOUBLE GUIDING TRACK Filed Aug. 21, 1964 3 Sheets-Sheet :5

7 y; 6 Q INVENTOR. v 6x026 4L/7Z4'0 Z/P cL Arman/5 1? United States Patent This invention relates to a file cabinet having carriers arrange-d on a pair of endless chains and adapted for carrying documentary material such as card boxes or pro- "vided with carrying rails for depending panels, pockets,

or similar. Each end of such carriers is connected to a supporting arm by means of a trunnion and to at least one such trunnion there is fastened an angle bracket nonrotatably therewith which serves to reverse the carriers to the opposite sides of suitably provided parallel guides. Said angle bracket is arranged with two guide rollers positioned at equal heights, which rollers in at least the region of the lower end of the chains and in the region of the vertical midplane of the chains are guided in two trackways arranged along side of the chains. One guide roller of each respective angle bracket is continuously engaged by one trackway.

In one such known file cabinet, as shown in United States Patent No. 2,912,118, each carrier arm comprises two single arm levers arranged in the form of shears. In such construction, levers are at their oneends common ,to the trunnions of a carrier and at their other ends they are connected at previously determined equally located intervals on the chains. An angle bracket nonrotatably fastened at least to the trunnion of each carrier is constructed as a triangular plate with two sides of equal length corresponding to the lever arms. Advantageously, the equal sides comprise a right angle. Each triangular plate is so fastened nonrotatalbly on the corresponding trunnions of the carrier that the base, that is the hypotenuse, runs parallel to the bottom of the carriers, that is for example, to the bottom of the file card boxes used as carriers. The outer one of the guide rollers located at the lower corners of each triangular plate is guided upon orbiting of the carrier through an endless track- Way. At the lower end of this trackway, there opens a further trackway tangentially and symmetrically about the vertical mid-plane located between the two rectilinearly running portions of the chains, said trackway comprising two branches which extend only through the reversing region of the carrier. At the upper end of the apparatus, there is provided only a single trackway, whereby the angle bracket supported guide rollers which cooperate with each trackway are guided only in the lower reversing zone of the carriers. At its upper end, the trackway has on its inner side only an appropriately provided opening so that the inner roller of each respective triangular bracket, which roller up to now has been unguided, canenter into said opening upon the reversal further trackways comprising two branches which act with the other roller of each angle bracket, which-trackways impede swingingmovement'which might otherwise occur'if a toggle comprised of acarrier arm and a lever Patented Jan. 17, 1967 arm together with the outer roller is created during movement through the lower turning region. In this lower position, in which the lengthwise axis of the respective carrier arms extends somewhat through the pivot position of the corresponding angle brackets and through the midpoint of the outer thusly guided roller of the corresponding lever arm, the pivot point comprising the trunnion of a given carrier becomes suddenly released as a result of further movement of the angle lever bracket and thereby in spite of the guiding of the outer guide roller there occurs a violent pendulum movement of the associated carrier since the roller is not guided in the direction of pendulum movement. This is, however, not a problem in the structure of United States Patent No, 2,912,118 by reason of the guiding of both guide rollers of each angle bracket at the lower turning region. In the upper turning region of said patent, the lineal positioning of the carrier arm and the lever arm with the outer roller cannot occur, so that the guiding of both guide rollers of the angle bracket is not necessary. Although the file constructed according to said patent is satisfactory in its operation with respect to the guiding of the carrier from one vertical course to the other, it is nevertheless undesirable with respect to the building of the carrier arm and with respect to the strain on the chains. In addition, the operation of the chains is noisy. Through the direct linking of both arms comprising a single carrier arm to the chains, the carriers apply in the lower turning region a continuous force tending to dislodge the chains from the teeth of the drive gears. Since it is known that chains under the stress of a high work load will lengthen rather quickly, there exists in the lower turning region, especially in the postion of the angle bracket, a continuous danger of the chains running 01f the rails. This is particularly true if an operator has neglected to inspect the chains carefully with respect to the likelihood of their stretching. Corresponding problems exist also in the upper turning region because in an inclined position of one carrier arm the one shear a-rm braces itself on the chain and the other shear arm tends to raise the chain from the drive gear.

Further, the chain in the straight-line part of the closed track is guided at both of its open sides, wherefore it cannot jump out of its proper position by reason of the considerable Weight of the associated carriers engaging each carrier arm. However, through friction of the straight-line portion of the chain against the metal guides there is created excessive noise as well as the considerable wear associated therewith. Further, the present designs are correspondingly undesirable because the guides of the angle bracket rollers, which are always located outwardly in the arrangement of a single drive wheel and guide part for one course of the chains, for example, on a comm-on base plate or indirectly on the side wall of a housing, requires a correspondingly wide base plate, particularly having stiffened side walls. In the known files, each lower chain drive gear is mounted adjustably in order that the lengthening of the chains through subsequent stretching can ,be equalized by adjustment of the chain drive gears. Since, however, no means at all are pro vided for the guiding of the rollers of the angle brackets appropriately to the alteration of the chain length, there must be provided from the outset an appreciable play for the rollers in the angle forming part of the trackways through which means the pendulum movement and swinging of the carriers in the turning region again occurs.

It is therefore thepurpose of the invention to so modify a known'file to retain the above-outlined features derived fromthe use of the angle brackets, providing for the advantageous guiding of the opposite parallel positioning of the carrier's so that the structural width of the gear area is at a minimum and each chain is fully held against coming out of its guided position and is practically noiseless.

According to the invention, this purpose is accomplished in that each carrier arm for a carrier is constructed from a two arm, essentially straight, lever with dissimilar lever arm lengths, in that each carrier arm is guided by short lever arms each provided with two spaced rollers located in an endless inside trackway running directly adjacent the chains and in that of the two rollers of each angle bracket, the inner roller engages constantly against the endless correspondingly arranged trackway. The two halves of said trackway are provided symmetricaly with respect to the vertical lengthwise midplane of the mechanism, cross in the region of the lengthwise midplane and in each turning region are guided over and beyond the intersection. Further, said trackways are so constructed that both rollers of each angle bracket are constantly guided at the same height at each turning region. It is further desirable to make the endless trackway adjustable in length by making the lower turning means adjustable as to height and the trackways are accordingly divided into tele scopically interengaging parts. In addition, the short lever arm of each carrier arm comprises an inverted T-shape and is provided at its flange ends with a roller, both said rollers being in engagement with the associated trackway running along the corresponding chain.

Each carrier arm is preferably constructed as an angular structure comprising a fork arranged on the side of the endless chain opposite, or remote from, the carriers but still close to the chain. Both fork blades are fixed in position by a suitable chain bolt. Such pivoting of the carrier arm on the chain is very advantageous on the basis of the equalization of forces. It can, however, in chains of known files not be accomplished, because there the chains slide between guides. Each chain bolt is received through fork blades of a corresponding carrier arm and is arranged to effect equalization of spacing in between each pivot point on the chain and the flanges of the short lever arms which are respectively guided in a trackway. Further, each trunnion of a carrier is supported for equalization of width differences of the carriers by axially adjustable hubs fixed at the corresponding ends of the carriers.

Through this construction there becomes needed, in contrast to the known files, a supplementary endless trackway. In this manner, the guide means for the straightline chain sections, which are the primary sources of noise, are eliminated so that the operational speed of the file can be increased. Especially will there be avoided carrier arms consisting of two levers and tending to cause derailment of the chains in the turning region and instead the effective force is carried directly on the side walls of the supplementary trackway so that the endless chain is required to take practically only the load derived from the weight of the carriers. It is very important also that in the adjusting of the chains, the intervals of the trunnons for the carriers from the respectively associated chains be not altered, whereas in the known files such an alteration of the intervals occurs because the shear-like arms utilized therein will upon subsequent stretching of the chains become spread apart from each other. Alteration of the intervals between the trunnions and the chains leads to an inclined position of the carriers, as seen from the sides, whereby the rollers of the triangular plates guided in the trackways works as a swing centering device. Such an inclined position of the carrier can lead to a condition such that the rollers of the triangular plate at the turning zone can no longer run in the open trackway so the rollers of the triangular plates must be forced out therefrom. Through the guiding of the inside rollers of the angle bracket there is obtained also a small structural width for the carrier positions and particularly for the base plate carrying the entire driving mechanism. The entire lower turning region with the part of the endless trackway associated therewith, including both branches and with the chain drive mechanism, can be constructed as a special construction part and the stretching of the chain is effected by a simultaneous elongating of the adjustably supported trackway. Especially the herein-described construction has the advantage that, for example, the supports for all the trackways lie in a common plane so that in a file having a given cabinet breadth the carriers can be provided with as great length as possible and thereby maximum volume for the file since each drive mechanism is provided preferably on each side with a correspondingly small thickness.

Gne embodiment of the invention is set forth in the drawing as follows:

FIGURE 1 is a perspective view of a file cabinet.

FIGURE 2 is a schematically elevational, inside view of a drive mechanism side of a file having endlessly orbitable carriers.

FIGURE 3 is a section on the line IIIIII through the lower turning region of the drive mechanism side of FIGURE 2 seen in the direction of the arrows.

FIGURE 4 is a detail view of a lengthwise adjustable trackway.

FIGURE 5 is a cross section through said last-named track on the line VV of FIGURE 4.

FIGURE 6 is a fragmentary section taken on the line VIVI of FIGURE 2.

The drive mechanism for a file cabinet with continuously orbitable carriers 1 is set forth in FIGURE 1 and can in a known manner be arranged on the inner side of each side wall 42 of, for example, a cabinet 41, desk, or similar. The cabinet, desk, or similar is provided at the operating side with an opening 43 through which several carriers can be called up by means of a selector and control mechanism energized by electric motor means for access to their contents in a most expeditious manner. Driving, selecting and control mechanism of this type, as well as the housing from which is provided the file, cabinet, desk or the like, are all well known and are therefore set forth in FIGURE 1 only schematically.

Since the two drive mechanisms are mirror images of each other, it will be sufficient to describe in detail only one thereof. Thus, referring to the drive mechanism according to FIGURE 2, there is set forth an endles chain :2 having both of its straight courses 3 preferably vertical- 1y arranged over an upper guide wheel 4 and around a lower guide wheel 5. Said straight courses may in some instances be inclined to the base without departing from .the scope of the invention. This type of both chains and guide wheels are well known in files of this type and therefore are set forth only in broken lines. Instead of the chain 2 there can also be utilized a belt or rope. Usually the lower wheels 5 in a file utilizing endless chains 2 are driven by an electric motor (not shown) over an appropriate chain drive mechanism and a reduction gear mechanism. Said motor is usually in engagement through a pinion to the shaft 6 which in turn connects to the lower wheels 5 of both drive sides. The upper and lower wheels 4 and 5, together with their comm-on shafts, can be mounted directly onto the correspondingly reinforced side walls of the file housing such as the cabinet 41, or if desired, on special plates 7 and 8 which are adjacent corresponding side walls 42. To each chain there are pivoted the carrier arms 9 in equal spacing for the reception of the carriers 1, carrier rails or similar. Carrier arms of this kind can assume different forms. In the illustrated example, each carrier arm 9 consists of a two-armed, straight lever with arms 10 and 11 of dissimilar length, and the endless chain 2 is arranged on the side opposite the carrier 1. Adjacent the chain, the carrier 1 is provided with a sideward projection 12 which, together with the straight long lever arm 10 of a given carrier arm constitutes the fork 13 embracing the chain on three sides. The two fork blades are penetrated by a chain blot 15 which is received adjustably in both fork blades by a slot 16 lengthwise of the carrier arm and provides a pivot point for the carrier arm in question on the chain 2. The short lever arm 11 of each carrier arm 2 has a T-form shape. A low friction roller 18 is mounted at each end of the cross bar 17 of the T, said cross bar being perpendicularto the length of the carrier arm and being located at the inner ends of each of the levers. .Said rollers 18 comprise a cylindrical, neck-like running surface 19 and further, a pair of adjacent truncated conical running surfaces20.

At the end of each carrier arm 9 opposite the chain bolt 15 and on the long lever arm 10, there is provided a bear- ,ing 21 which is mounted rotatably but nevertheless axially immovable with respect to a trunnion 22 of the carrier 1. Each trunnion 22 of a carrier can, for example, be fastened non-rotatably, nevertheless axially adjustably, in a hub 23 having a mounting flange 24 by means including a key 25. For theaxial adjustable fastening of the trunnion, the hub 23 may advantageously be constructed as a clamp housing, the key 25 being guided both adjustably and fixably in a correspondingly long keyway 26 of the respective trunnions 22. Such construction has the advantage that through the axial adjustability of each trunnion there can be accommodated relatively great length differences in carriers 1 resulting from the manufacture thereof and even also differences in the spacing of the side walls of such files involving cabinets, housings, desks, or similar. In this manner,the mass production of file cabinets of this type becomes greatly facilitated.

To the free end of at least one trunnion 22 of' each carrier, there is nonrotatably fastened an angle bracket 27 having arms of equal length. Said fastening is accomplished, for example, by means of recesses 28 providing a square shaft section at the apex of the angle bracket, and by means of a nut 29. At the free end of each of the bracket arms 30, there is mounted a low friction roller 31. The fastening of each angle bracket 27 on the corresponding trunnion 22 is accomplished so that the roller 31 of both angle arms 30 lie at equal spacings from the file base where each carrier 1, for example,

is built as a card carrier, particularly a card box. Obviously triangular plates or discs can be utilized advantageously in place of the angle bracket. It is only essential that both rollers upon the traveling of the carriers lie at equal heights whereby both lengthwise axes of the bracket arms 30 can extend perpendicularly to each other through the middle of the rollers and simultaneously through the trunnions of the carriers.

Within the loop defined by the endless chain 2 there is an endless guide track 32 arranged directly adjacent the drive mechanism side as seen in the elevational view. The narrow spacing of the track 32 from the chain follows from the fact that the short lever arm 12 has only a short length in contrast to the long lever arm of each carrier arm 9. The spacing of the midpoint of this track from the middle portion of the chain corresponds to the shortest spacing of the line connecting the two rollers 18 from the axis of the bolts 15. The track 32 runs constantly parallel to the endless chain 2. Since in each turning region the chain and the guide track both follow the arc of a circle, the bar 17 of each short lever arm 11 together constitute a straight line defining a chord of said arc, thus the distance of the corresponding chain bolts from the bar of the respective short lever arms is modified in the turning regions. Therefore, in order to assure freedom from binding of the respective carrier arms in the track 32, each chain bolt guided in a carrier arm 9 is arranged adjustably in the slot 16 of the fork prongs of the short lever arm 11.

There is further provided a guide track 33 at each of the respective paths of the outer rollers 31 which are constructed as two T-form mirror images with respect to each other, arranged as track halves defining courses 34 and 35. The two track portions 34 and 35 cross each other with their arcuate formed track parts 34a and 35a regions. The parts of their respective walls which cut across each other extend so that a track running endlessly thereto is provided in which there opens at the crossing zone two free outwardly running branches 34b and 35b of the arcuate formed track parts 34a and 35a. In this manner it is possible that upon the change in direction of a traveling carrier 1 at the intersection, the roller 31 of each angle bracket 27 which up to now was located inwardly becomes an outer unguided roller after the transit of the turning region, but each angle bracket is still guided by both rollers while it is in the turning region so that swinging of the carriers in the turning ,region will be effectively prevented.

Such swinging of the carriers in both turning regions is particularly likely to occur if avlever .arm 30 of an associated angle bracket should become parallel with the corresponding carrier arm 9, particularly if a straight .line can be extended through the chain bolt 15, the trunnion 22 and a roller 31 of the associated angle bracket as said carrier arm 9 comes out of the lower turning region of FIGURE 2. This would create a toggle which would cause a severe swinging of the connected'carriers upon the further operation of the chain and resulting urging of the carrier arms. Since the outer roller lying on the mentioned line has no guiding at all at the instant that the toggle is formed, there is nothing to hinder the swinging movement of the carriers within the guide track.

-,made out of metal, plastic or similar. The corresponding parts of the endless inner track32 for the carrier arm 9 and the mounting plate provided for the drive wheels 4 and 5 can be similarly made. The bearing mounting for the drive wheels is likewise made of a one-piece casting or molding which may be made of metal, plastic or similar. Such a casting has less structural thickness because the outer surfaces of all guide rollers lie in a single plane, see FIGURE 2. In consequence of the resulting lesser thicknesses for both drive mechanisms, the carriers extending between these drive mechanisms in a cabinet of given width can have a corresponding greater useful capacity.

Preferably the construction is so carried out that the plate 8 is adjustably mounted with respect to the drive mechanisms of the lower turning region of each chain 2 to alter the tension on a chain in the lengthwise direction of the straight portions of the chains. For this purpose there are provided in each plate 8 the slots 36 (FIG- URE 2) which serve for the fastening of a plate 8 by means of screws in a cabinet wall or to a suitable plate on a frame. For the tensioning of the chain 2, the fastening screws are loosened and the plate 8 is moved by means of an adjustable mechanism 37 to increase the spacing between the two wheels 4 and 5. Thereupon the fastening screws are again tightened.

In such a construction, the adjacent ends of the straight courses of the endless guide track 32 and the corresponding courses 34 and 35 of the endless guide track 33 preferably extend into a straight end 44 of the arcuate formed and correspondingly wide end portion of these guide tracks. In FIGURES 4 and 5 there is shown schematically such a construction only for the track 32. Flanges 38 are provided on the inner side of the track walls and extend inwardly to limit the width of the arcuate formed track part to the clear width of the straight sections of the guide track. In traveling from one track part, as the straight-line part, to another part of the same track, as the arcuate part, both the rollers 18 of the carrier arm 9, as Well as the rollers 31 of the angle bracket 27, can by the foregoing-described means travel shock-free from one track to the other track because at the place at which the rollers are no longer guided by the straight course of the track the flanges 38 of the arcuate formed track take over the guiding.

The upper mounting plate 7 can be arranged fixedly with the corresponding drive mechanism of the upper turning region and by means of the openings 39 and corresponding screws may be fastened to the respective cabinet Walls.

Although particular preferred embodiments of the invention have been disclosed above in detail for illustrative purposes, it will be recognized that variations or modificationsof such disclosure, which come within the scope of the appended claims are fully contemplated.

What is claimed is:

1. File structure having carriers for file material mounted on two endless chains wherein trunnions are provided at each end of the carriers and connected to carrier arms and at least one trunnion is fastened through an angle bracket and two outer rollers for holding the carriers parallel with respect to each other in all positions around their orbit within the file structure and wherein there is an inner trackway and an outer trackway running parallel in the region of the straight-line portion of the chains and wherein the rollers of each angle bracket are constanting held and guided within said outer trackway, characterized in that:

there is provided a carrier arm on each end of said carriers, each of said carrier arms being provided with two lever arms of unequal length, the short arm thereof being provided with two inner rollers which are guided in said inner trackway and further characterized in that at least one of the two outer rollers is continuously engaged with the outer trackway, and further characterized in that portions of the outer trackway cross each other in the vertical 40 plane extending midway between the straight-line portions of the chains, the spacing of said outer trackway being arranged with respect to the path of said chain so that said outer rollers are guided with their axes held in a substantially horizontal plane.

2. A file according to claim 1 characterized in that the endless guide tracks are all adjustable in length so that at least the lower turning region is adjustable with respect to a mounting plate and the track is divided into telescopingly interengaging parts.

3. A file according to claim 1 characterized in that the short lever arm of each carrier arm is T-shapcd and the ends of the short lever arm are provided with the inner rollers both of which are in engagement with the inner trackway.

4. A file according to claim 1 characterized in that the carrier arm is arranged on the side of the chain opposite to the carriers and in the region of the chain extends as an angular projection terminating in a fork of which both fork prongs are penetrated by a chain bolt.

5. A file according to claim 4 characterized in that each corresponding chain bolt is guided in the fork prongs of the corresponding carrier arm, said chain bolts being mounted in a slot for accommodating the changes in spacing of said chains from said inner track as the mounting of said inner rollers becomes a chord of the arc of the end guide tracks.

6. A file according to claim 1 characterized in that each trunnion of a carrier is supported for accommodating the differences in length of the carriers by axial adjustment of the hubs in one of the corresponding ends of the carriers.

References Cited by the Examiner UNITED STATES PATENTS 2,125,619 8/1938 Parent 312-266 2,603,547 7/1952 Zook 312223 2,703,643 3/1955 Parsons 198137 2,912,118 11/1959 Behrens et al 211121 CLAUDE A. LE ROY, Primary Examiner.

K. I. WINGERT, Assistant Examiner. 

1. FILE STRUCTURE HAVING CARRIERS FOR FILE MATERIAL MOUNTED ON TWO ENDLESS CHAINS WHEREIN TRUNNIONS ARE PROVIDED AT EACH END OF THE CARRIERS AND CONNECTED TO CARRIER ARMS AND AT LEAST ONE TRUNNION IS FASTENED THROUGH AN ANGLE BRACKET AND TWO OUTER ROLLERS FOR HOLDING THE CARRIERS PARALLEL WITH RESPECT TO EACH OTHER IN ALL POSITIONS AROUND THEIR ORBIT WITHIN THE FILE STRUCTURE AND WHEREIN THERE IS AN INNER TRACKWAY AND AN OUTER TRACKWAY RUNNING PARALLEL IN THE REGION OF THE STRAIGHT-LINE PORTION OF THE CHAINS AND WHEREIN THE ROLLERS OF EACH ANGLE BRACKET ARE CONSTANTING HELD AND GUIDED WITHIN SAID OUTER TRACKWAY, CHARACTERIZED IN THAT: THERE IS PROVIDED A CARRIER ARM ON EACH END OF SAID CARRIERS, EACH OF SAID CARRIER ARMS BEING PROVIDED WITH TWO LEVER ARMS OF UNEQUAL LENGTH, THE SHORT ARM THEREOF BEING PROVIDED WITH TWO INNER ROLLERS WHICH ARE GUIDED IN SAID INNER TRACKWAY AND FURTHER CHARACTERIZED IN THAT AT LEAST ONE OF THE TWO OUTER ROLLERS IS CONTINUOUSLY ENGAGED WITH THE OUTER TRACKWAY, AND FURTHER CHARACTERIZED IN THAT PORTIONS OF THE OUTER TRACKWAY CROSS EACH OTHER IN THE VERTICAL PLANE EXTENDING MIDWAY BETWEEN THE STRAIGHT-LINE PORTIONS OF THE CHAINS, THE SPACING OF SAID OUTER TRACKWAY BEING ARRANGED WITH RESPECT TO THE PATH OF SAID CHAIN SO THAT SAID OUTER ROLLERS ARE GUIDED WITH THEIR AXES HELD IN A SUBSTANTIALLY HORIZONTAL PLANE. 